In an existing mobile communication system, an operator provides a Subscriber Identity Module (SIM) card for a user, and a cellular system uses the SIM card provided by the operator for identity authentication. A user need to apply to different operators for SIM cards respectively in order to use services provided by the operators. Moreover, when an SIM card is lost or damaged, the user may not access the network of the operator and thus may not use the service.
In addition, since a phone number may be used by only one terminal device at the same time, when a user wants to replace his/her terminal device, the SIM card has to be transferred to the substitute at the same time. However, at present, different terminal devices have different specification requirements on SIM cards. Therefore, when replacing the terminal device, the user may have to go to the operator to replace the SIM card or use an adapter. This may bring inconvenience to the user, cause high overhead of the user and even damage the SIM card or the terminal device due to failure of the adapter.
In view of the above, the existing manner makes many limits to a user's usage of a service of an operator, brings great inconvenience to the user and may even cause high overhead of the user.